Fitting the right tyres on loading and hauling equipment can save quarrying sector businesses money through their increased longevity. Guy Woodford reports
If your child enjoyed erasing the gritty coating on sandpaper, you would probably tell him or her to stop, avoiding any potential for upset at seeing the eraser erode and vanish within minutes. But if the sandpaper was a sandstone quarry, and the eraser the tyres of a dump truck transporting 100tonne loads, 12 hours a day, the matter would be far more serious. That’s the scenario at a quarry in Piesberg, near Osnabrück in Germany, where the sandstone extracted is rich in quartz and considered to be one of the hardest and most abrasive materials in the world. It is used not only as a raw material to make cement and asphalt, but also for road and hydraulic construction purposes.
Top priority for Ralf Schmidt, head of purchasing for
Schmidt took action and set up a meeting with technicians from White, a trusted Cemex dealer, and experts from Bohnenkamp, official importer of
BKT offered its quarry-suited Earthmax radial tyre series designed to foster better load distribution on the ground for all dumpers, wheeled loaders and earthmoving vehicles that are exposed to harsh operating conditions. Of the 11 tyres in the line-up, the Bohnenkamp technicians chose only one: Earthmax SR 45. Schmidt was advised that this tyre version was ideal for rigid dumpers. The tyre’s all-steel casing, and the extra deep tread along with the special cut-and abrasion-resistant compound were said to be able to guarantee a longer lifecycle, even in extreme working environments. “I couldn’t wait to test the BKT tyres,” admitted Schmidt, “and was surprised at how such a competitively priced product could complete a life cycle of 2,000 hours withstanding the same harsh conditions found at the quarry in Piesberg.”
The first set of 4 Earthmax SR 45 tyres that Schmidt bought were twin mounted on the rear axle of a Cemex dumper, demonstrating extraordinary resistance and reliability. Last summer, they terminated their life cycle after over 2,000 operating hours. The success of the Earthmax tyres gave White’s service centre a huge boost. Special tyre replacement devices helped Cemex resolve what had become a major headache for the company.
“Downtime is our main cost related to dumpers,” said Schmidt. “The new BKT tyres demonstrated exceptional resistance to wear and cuts, never requiring downtime for repairs, and White’s tyre replacement systems brought the downtime gap for tyre replacement to just three hours.”
After the Earthmax SR 45 passed the rear axle trial run with flying colours, Schmidt is looking forward to testing BKT’s latest tyre, the Earthmax SR 47, on the front axle of the quarry’s dumpers.
The E4 marked Earthmax SR 47 tyre is said to be longer lasting because of its extra deep tread design. Furthermore, its special lug design ensures regular tread wear as well as excellent traction. These features are ideal for tyres that are used in harsh environments such as Piesberg quarry.
At Rennig Beton quarry in Germany, Camoplast Solideal has been closely following tests on the longevity of its SRGP23.5R25 33mm tread depth radial tyres for articulated dump trucks, wheeled loaders and motor graders. After 3,126 hours of service on a
The first right rear tyre had 11mm of tread left after 3,126 hours and the second right rear tyre had 15mm of tread, equating to 142 hours and 173 hours per lost mm of tread respectively.
What Camoplast Solideal has found in the ongoing tests at the Rennig Beton quarry in Obermeitingen, Bavaria is that if you rotate the rear tyres, their longevity increases. Where the rear left and rear right tyres aren’t rotated they perform an average of 3,676 hours and 4,660 hours respectively before needing to be changed due to lack of tread. But if rotated, the rear left and rear right tyres perform for an average of 3,783 hours and 3,810 hours respectively – allowing both rear tyres to be removed at the same time.
Meanwhile, after 3,462 hours of testing on a Moxy-MT 31 with the same 20-22tonne average payload, the left front and right front SRGP23.5R25 tyres had 13mm of tread remaining, equating to 173 hours of service per lost mm of tread.
The Moxy-MT 31 at Rennig Beton being used in the continuing Camoplast Solideal test is the first ADT in the EU mounted with six SGRP- 23.5R25 dual-star tyres. The tyres dual-star construction is said to be long lasting, offering enhanced stability and retreading, as well as excellent puncture resistance.
The latest tyre test follows on from another by Camoplast Solideal at Rennig Beton involving SRGP-23.5R25 tyres on a
After 8,114 subsequent operating hours, the SRGP-23.5R25 tyres had an average 11mm of tyre tread remaining. These tyres are said to have outperformed the ones from the competitor brand by 2,028 hours or 33%. Camoplast Solideal said that despite abrasive underfoot conditions during the test, the SRGP treads appearance remained excellent, the Case 821C operator did not force the WHL transmission to fill the bucket against the pit wall, no rear tyre spins were visible during the loading and transporting, and the engine RPM on the 821C was kept in a constant and low level.
As well as being a leading specialist in the design, manufacturing, and distribution of off-road tyres, the Camoplast Solideal also manufactures wheels, rubber tracks, and undercarriage systems serving the material handling, construction, agriculture, powersports, and defence industries.
The new retread tyres are made using Recaflex technology and featuring deeper tread E4 and L4 patterns. The non-directional profile, used on articulated dumpers and loaders, is said to feature excellent traction and high resistance to cuts and chipping during operation. The ‘self-cleaning’ tread has a deep and solid pattern that gives the profile stability even on soft ground (mud) and strength on rough and aggressive terrain (stones/rocks).
The flexibility of its R&D centre and close collaboration with customers allows Marangoni Earthmover Tyres to customise its products and propose patterns to suit the casing to be retreaded, the pattern depth and the consequent outside diameter of the retreaded tyre. Making purposely-designed compounds for individual applications means that diverse user requirements can be fulfilled.
By adopting a high-quality retreading process, Marangoni claims its Marix tyres can ensure excellent performance levels that are equivalent to those of premium-brand new tyres, guaranteeing considerable reductions in cost per application hour and meeting crucial market efficiency needs. As well as being an excellent solution to give premium brand tyres a second life, Marix retreaded tyres are also said to be extremely competitive against low-cost Asian-made new tyres, as well as having a claimed much lower cost per application hour.
At the company’s Rovereto plant, a new machine is being installed that uses shearographic technology to identify all possible defects, both during initial casing inspection and final testing of the retreaded product, thus further improving the already high quality standards of Marangoni Marix retreaded earthmover tyres.
Dutch off-highway tyre manufacturer
Magna MA08 is said to be designed for use on wheeled loaders requiring maximum traction. The aggressive, open tread pattern provides extra traction and stable ground contact. Therefore, this tyre is perfectly suitable for wheeled loaders running at open pit mines, underground mines and stone quarries.
At
Constantly innovating,
Latest innovations from Erlau include the claimed revolutionary Easy R-Lock, said to eliminate the dangers of the hammer, the steel pin and the cutting torch with an integral, hex-key-operated, two-piece locking device. The reusable Easy R-Lock is said to bring both safety and time-saving to TPC installation and dismantling and, in so doing, reduces the risk of exploding tyres.
Meanwhile, Easy C-Lock is said to come into its own on the rare occasion of replacing a wear link. Until now, Erlau says common practice has been to secure the replacement link by hammering home a non-removable, steel pin. Now, the one piece, forged, steelalloy Easy C-Lock is quickly secured and removed by rotating the integral locking device through 180° using a conventional flat-head screwdriver.
Erlau’s Smart-Link is a link-embedded RFID-based memory which records a downloadable service history of each TPC, enabling managers to track and evaluate lifeof- chain performance.
A departure from the traditional, steelalloy protection chain, Sideflex is said to be a revolution in the evolution of sidewall protection for large haul truck tyres. Adapting automotive memory polymers, Sideflex’s lightweight, flexible, deflecting shield is claimed to offer truck owners the first viable solution to the danger of sidewall penetration from stray flints and sharp, shale-type rocks.
